With the less than estatic response to Vista it struck me that what is needed is a common sense approach to this...
Vista in many ways is 'where its at' as a developer there are a lot of features that are already there for you to use - .Net 3 for instance but it feels that unless you have a very good machine of vintage two seconds ago it runs like a dog!! This means to a great extent your productivity takes a bashing! The other issue with Vista with less than cutting edge kit is the problem of drivers or rather the lack of them!
So the answer, I think, is dual booting - if your Vistaed up the have a look at VistaBootPRO 3.3 (About VBP 3.3) to help you solve the booting issues.... - so you dual boot XP and Vista and have the best of both worlds.
On of the clever things to do of course is when re-installing Office, Visual Studio and the like is to install into the directories of the the other boot...for example install all the apps you need in Vista the boot to XP and re-install but in the Vista program locals.
This reduces the footprint of the install whilest making it all available in both modes.
Good booting!!